Peter's Vehicles are a running gag involving Peter Griffin using a comedic mode of transportation to get a task done often to disastrously hilarious results. They often have the word "Peter" in them, and often says "To the [mode of transportation here]".
The Petercopter
In "The Cleveland-Loretta Quagmire", Peter goes to Quagmire's house to warn him about Cleveland and uses the "Petercopter." It ends up crashing in Joe Swanson's yard. It's also mentioned in "Dog Gone".
In "Inside Family Guy", it is used by Seal Team 6 in the killing of Osama bin Laden.
Cleveland reveals that he gets first dibs on the items that Peter looses interest in and acquires the Petercopter in "Nanny Goats", turning it into the "Clevelandcopter." Unfortunately, he crashes it into a house when he can't see through the mustache.
The Hindenpeter
In the same episode, Peter used a blimp called the "Hindenpeter", which crashes in Joe's yard following the previous wreck of the Petercopter.
The Peterdactyl
In "Quagmire and Meg", Peter attempts to ride a pterodactyl in his likeness but he accidentally crashes it into live wires and it is electrocuted, so Peter has to take care of its babies.
The Peterang
Peter tries to use the Peterang to rush Scotty to the hospital in "Livin' on a Prayer". When the giant, piloted boomarang is launched from a catapult, he manages to briefly go to the hospital before being returned to the house.
The Megcopter
Peter becomes friends with Meg in "Meg Stinks!" and supplies her with her own "Megcopter" so they may hang out together. As they fly away, Peter observes Retep killing a lady.
Miscellaneous
In a behind-the-scenes look at the show in "Inside Family Guy", host James Woods leads the tour though the prop shop which features many unnamed vehicles, including a van, a rocket, a motorcycle with sidecar and a Segway.